Self filling fountain pen



'Sept. 29,1936. E. s. sEARs sELF FILLING FOUNTAIN PEN Filed Oct. 11,1955 Jmm v EDWARD fiTfPHEN SEHRS,

Guam:

Patented Sept. 29,

UNITED STATES SELF FILLING FOUNTAIN PEN Edward Stephen Sears,

Oxhey, England, assignor to Mabie, Todd & Company, Limited, London,

England Application October 11, 1935, Serial No. 44,579 In Great BritainOctober 31, 1934 7 Claims.

The objects of the invention are, inter alia, to provide a pen of simpleand neat construction, having a relatively large ink carrying capacity,:and one-which can be adapted to give a visible indication when thereservoir of the pen needs replenishment or when the ink reservoir isfull or approximately so.

The present invention accordingly consists in a self-filling fountainpen comprising in combination, a writing point section, a duct passingthrough the said section, an air tube having one end fixedwithin thewriting point section and in communication with the duct, an inkreservoir'adapted to envelop the projecting portion of the air tube andcomprising a rigid tubular plunger, and an aligned flexible open endedtubular member connected to the tubular plunger, the outer end of thetubular plunger being closed, the opposite flexible end of the reservoirbeing functionally secured to the inner end of the writing pointsection, and resilient means disposed between the rigid plunger and theinner end of the writing point section, the rigid plunger being directlyurged toward the writing point section to reduce the capacity of theflexible portion of the reservoir by endwise pressure, thepartsautomatically returning to their normal position by the operationof the resilient means when the endwise pressure on the plunger isremoved whereby ink is adapted to enter the reservoir.

- The invention also consists in a fountain pen according to thepreceding paragraph, further characterized in that the open end of thesleeve plunger is in direct fluid-tight association with one end of aflexible and resilient member which is connected to the inner end of thewriting point section. The sleeve plunger (hereinafter referred to asthe plunger) is adapted to be reciprocated in an end-wise direction overa further tubular member (hereinafter referred to as the air tube). thesaid air tube extending longitudinally through the ink reservoir andhaving one end in fixed relation to, and in open communication with thewriting point.

The-invention still further consists in a fountain pen according toeither of the preceding paragraphs, characterized in that the plunger isformed wholly or partially of transparent or translucent material so asto give a visible indication when the reservoir of the pen needsreplenishment or when the ink reservoir is full or approximately so. 7The invention will now be described with the aid of the accompanyingdrawing in which:-

Fig. 1 is a longitudinal section of one form which the invention maytake;

Fig. 2 is a partially dismantled view of the pen shown in Fig. 1; and

Fig. 3 is a view partly sectional of a modified detail of the pen shownin Figs. 1 and 2.

Referring now to Figs. 1 and 2 of the drawing, the pen comprises aplunger l which takes the form of a sleeve closed at its upper end andadapted to form part of the ink reservoir A. The opposite and open endof the plunger I is connected in an airand fluid-tight manner to aflexible and resilient tubular member 3 adapted to form the second partof-the ink reservoir and the opposite end of which is similarlyconnected to the inner end of the writing point section 5. Both theinner end of the plunger I and the inner end of the writing pointsection 5 may be formed with a lip as shown, to facilitate attachment ofthe member 3. 20

That part only of the plunger l adapted to project from the end of thebarrel is preferably made of transparent or translucent material, or thewhole of the plunger may be so made. The flexible and resilient member 3may be made of soft rubber.

The plunger I is adapted to be reciprocated in an endwise direction overan air tube 6 which is secured in a bore in the feed bar 8 positioned inthe writing point section 5 carrying the nib [0. A lateral duct ll putsthe air tube 6 into communication with the ink groove I2 in the feedbar. The

plunger I is adapted to be moved by hand toward the writing pointsection 5 and to be returned by reason of the resiliency of the member 3assisted by the action of the helical spring l3.

The assembly above defined (marked B in Fig. 2) is adapted to bepositioned in a barrel l4, one end of which is secured by screwing at Hito the writing point section and through the opposite end 16 of whichthe closed outer end of the plunger l is adapted to protrude for thepurpose of manual manipulation.

To facilitate its movement the plunger is formed with a part I! ofslightly greater diameter than the protruding portion, this surface I!being of such size as to be a sliding fit within the interior of thebarrel I4 which thus acts as a guide for the plunger and also provides ashoulder l8 which, in association with a confronting shoulder H! on theinterior surface of the barrel l4, acts as a stop to limit the outwardmovement of the said plunger. 7

The stroke of the plunger should preferably be equal to, or onlyslightly less than, the distance between the end of the air tube and theend of the plunger when the latter is in its outer position.

That end of the plunger adapted to project through the end of the barrelis protected by a short cap 29 when the pen is in use, which cap may besecured by screwing to the outer end of the barrel as shown. The writingpoint end of the barrel I4 is also .screwed at Zl to take a cap 22 ofthe usual kind, when the pen is not in use.

The operation of filling the pen is as follows:

The protective cap 20 for the plunger is first removed, after which thewriting point and part of the writing point section 5 are immersed inthe ink supply. A part of the air within the reservoir is then expelledby pressing the plunger towards the writing point, the resilient tubularmember 3 being collapsed in end-wise or cone certina-like manner and thedisplaced air, passing by way of the air tube 6 through thewriting'point section to the ink supply from whence it rises to thesurface. Upon the release of the pressure on, the plunger, the latter isreturned to its normal position under the influence of the resilienttubular member assisted by the spring 13, ink passing from the supplyupward through the usual ink channel l2 in the feed bar 8, and also, inlesser quantity, upward throughthe air tube 6, to the interior of thereservoir A.

This operation is repeated until no more bubbles appear on the surfaceof the ink supply,

or in the case of a transparent or translucent.

plunger, that part projecting through the barrel gives a visibleindication that the reservoir is full, after which the pen can be.removed from the ink supply and the protective cap- 20 positioned overthe projecting end of the plunger, whereupon the pen is ready for use.

Fig. 3 shows a modified form of flexible and resilient member whereinthe spring l3e is.embedded in the wall of the tubular member 3 which maybe of rubber or other flexible material or of flexible but non-resilientmaterial.

In a further modification the spring. can be located within theresilient tubular member.

Means may be provided to prevent relative rotary movement between thehollow plunger and the barrel or casing, and thus avoid the possibilityof inadvertently twisting the resilient tubular member where suchisused, and thus cause leakage. The means may conveniently consist inmaking that part of the plunger passing through the barrel or casing ofpolygonal cross section and correspondingly forming the end of thebarrel.

The outer barrel and the Writing point section together with theprotective caps may be made of opaque material to meet practical oraesthetic requirements, for example, vulcanite, opaque or figuredcelluloid or similar material may be used. The plunger I prefer to makeof transparent or translucent material, as, for example, glass,celluloid, or the like, whereby the protruding end of the said plungerwill form a ready indication when the reservoir of the pen is full orneeds replenishment.

I wish it to be understood that various modi fications in the details ofconstruction hereinbefore described may be made within the scope of myinvention.

What I claim and desire to secure by Letters Patent is:-

1. A self-filling fountain pen comprising in combination, a writingpoint section, a duct passing through the said section, an air tubehaving one end fixed within the writing point section and incommunication with the duct, an ink reservoir adapted to envelop theprojecting portion of the air tube and comprising a rigid tubularplunger, and an aligned flexible open ended tubular member connected tothe tubular plunger, the outer end of the tubular plunger being closed,the opposite flexible end of the reservoir, being functionallysecured'to the inner-end -0f'thewriting point section, and resilientmeans disposed between the rigid plunger and the inner end of the byforming-the, open-ended tubular member; of;

a suitable resilient material;

3. A self-filling fountain pen according to; claiml, wherein the res lent means is constituted by a helical spring;

4. A self-filling fountain pen accordingto, claim l'wherein theresilient means is constituted by forming the open ended tubular member;of a suitable resilient material supplemented a; helical spring.

5. A self-filling, fountain; pen; cq prising in combination, a writingpoint-section, a ductpass ing through the said section, anair tubehaving one end fixed within the writing point, section and incommunication With'thC duct, an ink res; ervoir adapted to envelop theprojecting portion; of the air tube and comprising a rigid tubula;r;plunger, and an aligned flexible open ended'tllblla lar memberconnected. to the tubular; plunger.- the outer end of the tubularplunger being; closed, the opposite flexible end of thereservoir, beingfunctionally secured to the inner end-of the writing point section,resilient means disppsed; between the rigidplungerand the inner endf thewriting point section, and an outer barrel having one end rigidlysecured to the writing point. section and serving as. a; uide fortheplunger, the outerendof whichistadapted to protrude therefrom. tofacilitate direct manual movement of the said plunger.

6. A. self-filling fountain pen, comprisingin combination, a writingpointsection, a duct pass: ing through the saidsection, an air tube,having one, end fixed within the. writing point section and incommunication, with the duct, an; inlg reservoir adapted .to envelop theprojectingppr tion of the air tube and comprising a rigid tubu lartransparent or translucent plunger, an an aligned flexible open endedtubularmembencon nected to the tubular plunger-,- the outer endf of thetubular plunger being closed, thev opposite flexible endof the reservoirbeing, functionally secured to the inner end of the; writing point sec,-tion, and resilient means disposed between the rigid plunger and theinnerendof the writing point section.

7. A self-filling. fountain pen comprisingln combination, a writingpoint section, a duct pass ing through the said section, an air tubehaying one end-fixed within the writingpointsection and incommunicationwith the duct; an inlg reservoir adapted to envelop the projecting-pention of the airtube and comprisingarigidtubular plunger, and; analigned; flexibleopen; ended tubular member connected to the tubularplunger, the outer end of the tubular plunger being closed, the oppositeflexible end of the reservoir being functionally secured to the innerend of the writing point section, resilient means disposed between therigid plunger and the inner end, of the writing point section, and anouter barrel having one end rigidly secured to the writing point sectionand serving as a guide for the plunger, the outer end of which isadapted to protrude therefrom to facilitate direct manual movement ofthe said plunger the protruding portion having a 5 transparent ortranslucent wall.

EDWARD STEPHEN SEARS.

